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diff --git a/api/2.6/Crypto.Cipher.ARC4-module.html b/api/2.6/Crypto.Cipher.ARC4-module.html new file mode 100644 index 0000000..7e81581 --- /dev/null +++ b/api/2.6/Crypto.Cipher.ARC4-module.html @@ -0,0 +1,254 @@ +<?xml version="1.0" encoding="ascii"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + <title>Crypto.Cipher.ARC4</title> + <link rel="stylesheet" href="epydoc.css" type="text/css" /> + <script type="text/javascript" src="epydoc.js"></script> +</head> + +<body bgcolor="white" text="black" link="blue" vlink="#204080" + alink="#204080"> +<!-- ==================== NAVIGATION BAR ==================== --> +<table class="navbar" border="0" width="100%" cellpadding="0" + bgcolor="#a0c0ff" cellspacing="0"> + <tr valign="middle"> + <!-- Home link --> + <th> <a + href="Crypto-module.html">Home</a> </th> + + <!-- Tree link --> + <th> <a + href="module-tree.html">Trees</a> </th> + + <!-- Index link --> + <th> <a + href="identifier-index.html">Indices</a> </th> + + <!-- Help link --> + <th> <a + href="help.html">Help</a> </th> + + <!-- Project homepage --> + <th class="navbar" align="right" width="100%"> + <table border="0" cellpadding="0" cellspacing="0"> + <tr><th class="navbar" align="center" + ><a href="http://www.pycrypto.org/">PyCrypto.org</a></th> + </tr></table></th> + </tr> +</table> +<table width="100%" cellpadding="0" cellspacing="0"> + <tr valign="top"> + <td width="100%"> + <span class="breadcrumbs"> + <a href="Crypto-module.html">Package Crypto</a> :: + <a href="Crypto.Cipher-module.html">Package Cipher</a> :: + Module ARC4 + </span> + </td> + <td> + <table cellpadding="0" cellspacing="0"> + <!-- hide/show private --> + <tr><td align="right"><span class="options" + >[<a href="frames.html" target="_top">frames</a + >] | <a href="Crypto.Cipher.ARC4-module.html" + target="_top">no frames</a>]</span></td></tr> + </table> + </td> + </tr> +</table> +<!-- ==================== MODULE DESCRIPTION ==================== --> +<h1 class="epydoc">Module ARC4</h1><p class="nomargin-top"></p> +<p>ARC4 symmetric cipher</p> +<p><a class="rst-reference external" href="http://en.wikipedia.org/wiki/RC4" target="_top">ARC4</a> (Alleged RC4) is an implementation of RC4 (Rivest's Cipher version 4), +a symmetric stream cipher designed by Ron Rivest in 1987.</p> +<p>The cipher started as a proprietary design, that was reverse engineered and +anonymously posted on Usenet in 1994. The company that owns RC4 (RSA Data +Inc.) never confirmed the correctness of the leaked algorithm.</p> +<p>Unlike RC2, the company has never published the full specification of RC4, +of whom it still holds the trademark.</p> +<p>ARC4 keys can vary in length from 40 to 2048 bits.</p> +<p>One problem of ARC4 is that it does not take a nonce or an IV. If it is required +to encrypt multiple messages with the same long-term key, a distinct +independent nonce must be created for each message, and a short-term key must +be derived from the combination of the long-term key and the nonce. +Due to the weak key scheduling algorithm of RC2, the combination must be carried +out with a complex function (e.g. a cryptographic hash) and not by simply +concatenating key and nonce.</p> +<p>New designs should not use ARC4. A good alternative is AES +(<a href="Crypto.Cipher.AES-module.html" class="link">Crypto.Cipher.AES</a>) in any of the modes that turn it into a stream cipher (OFB, CFB, or CTR).</p> +<p>As an example, encryption can be done as follows:</p> +<blockquote> +<pre class="py-doctest"> +<span class="py-prompt">>>> </span><span class="py-keyword">from</span> Crypto.Cipher <span class="py-keyword">import</span> ARC4 +<span class="py-prompt">>>> </span><span class="py-keyword">from</span> Crypto.Hash <span class="py-keyword">import</span> SHA +<span class="py-prompt">>>> </span><span class="py-keyword">from</span> Crypto <span class="py-keyword">import</span> Random +<span class="py-prompt">>>></span> +<span class="py-prompt">>>> </span>key = b<span class="py-string">'Very long and confidential key'</span> +<span class="py-prompt">>>> </span>nonce = Random.new().read(16) +<span class="py-prompt">>>> </span>tempkey = SHA.new(key+nonce).digest() +<span class="py-prompt">>>> </span>cipher = ARC4.new(tempkey) +<span class="py-prompt">>>> </span>msg = nonce + cipher.encrypt(b<span class="py-string">'Open the pod bay doors, HAL'</span>)</pre> +</blockquote> + +<!-- ==================== CLASSES ==================== --> +<a name="section-Classes"></a> +<table class="summary" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Classes</span></td> +</tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.ARC4.ARC4Cipher-class.html" class="summary-name">ARC4Cipher</a><br /> + ARC4 cipher object + </td> + </tr> +</table> +<!-- ==================== FUNCTIONS ==================== --> +<a name="section-Functions"></a> +<table class="summary" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Functions</span></td> +</tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <table width="100%" cellpadding="0" cellspacing="0" border="0"> + <tr> + <td><span class="summary-sig"><a href="Crypto.Cipher.ARC4-module.html#new" class="summary-sig-name">new</a>(<span class="summary-sig-arg">key</span>, + <span class="summary-sig-arg">*args</span>, + <span class="summary-sig-arg">**kwargs</span>)</span><br /> + Create a new ARC4 cipher</td> + <td align="right" valign="top"> + + + </td> + </tr> + </table> + + </td> + </tr> +</table> +<!-- ==================== VARIABLES ==================== --> +<a name="section-Variables"></a> +<table class="summary" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Variables</span></td> +</tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a name="block_size"></a><span class="summary-name">block_size</span> = <code title="1">1</code><br /> + Size of a data block (in bytes) + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a name="key_size"></a><span class="summary-name">key_size</span> = <code title="xrange(1, 257)">xrange(1, 257)</code><br /> + Size of a key (in bytes) + </td> + </tr> +</table> +<!-- ==================== FUNCTION DETAILS ==================== --> +<a name="section-FunctionDetails"></a> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Function Details</span></td> +</tr> +</table> +<a name="new"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <table width="100%" cellpadding="0" cellspacing="0" border="0"> + <tr valign="top"><td> + <h3 class="epydoc"><span class="sig"><span class="sig-name">new</span>(<span class="sig-arg">key</span>, + <span class="sig-arg">*args</span>, + <span class="sig-arg">**kwargs</span>)</span> + </h3> + </td><td align="right" valign="top" + > + </td> + </tr></table> + + Create a new ARC4 cipher + <dl class="fields"> + <dt>Parameters:</dt> + <dd><ul class="nomargin-top"> + <li><strong class="pname"><code>key</code></strong> (byte string) - The secret key to use in the symmetric cipher. +It can have any length, with a minimum of 40 bytes. +Its cryptograpic strength is always capped to 2048 bits (256 bytes).</li> + </ul></dd> + <dt>Returns:</dt> + <dd>an <a href="Crypto.Cipher.ARC4.ARC4Cipher-class.html" class="link">ARC4Cipher</a> object</dd> + </dl> +</td></tr></table> +</div> +<br /> +<!-- ==================== NAVIGATION BAR ==================== --> +<table class="navbar" border="0" width="100%" cellpadding="0" + bgcolor="#a0c0ff" cellspacing="0"> + <tr valign="middle"> + <!-- Home link --> + <th> <a + href="Crypto-module.html">Home</a> </th> + + <!-- Tree link --> + <th> <a + href="module-tree.html">Trees</a> </th> + + <!-- Index link --> + <th> <a + href="identifier-index.html">Indices</a> </th> + + <!-- Help link --> + <th> <a + href="help.html">Help</a> </th> + + <!-- Project homepage --> + <th class="navbar" align="right" width="100%"> + <table border="0" cellpadding="0" cellspacing="0"> + <tr><th class="navbar" align="center" + ><a href="http://www.pycrypto.org/">PyCrypto.org</a></th> + </tr></table></th> + </tr> +</table> +<table border="0" cellpadding="0" cellspacing="0" width="100%%"> + <tr> + <td align="left" class="footer"> + Generated by Epydoc 3.0.1 on Thu May 24 09:02:36 2012 + </td> + <td align="right" class="footer"> + <a target="mainFrame" href="http://epydoc.sourceforge.net" + >http://epydoc.sourceforge.net</a> + </td> + </tr> +</table> + +<script type="text/javascript"> + <!-- + // Private objects are initially displayed (because if + // javascript is turned off then we want them to be + // visible); but by default, we want to hide them. 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